There is considerable evidence for a co-morbid relationship between cocaine abuse and risky sexual behavior. Clinical studies have shown a correlation between cocaine use and risky sexual practices such as increased frequency, an increased number of partners, and unprotected sex. These sexual practices have been linked to adverse health consequences including high prevalence rates for sexually-transmitted diseases. Controlled preclinical studies that utilize animal models have demonstrated that prior repeated exposure to cocaine enhances sexual motivation and behavior. However, no parametric or systematic studies further investigating the basic mechanisms underlying this relationship have been conducted. The goal of the proposed experiments is to utilize an animal model whose sexual behavior system has been well-studied, Japanese quail. In addition to the benefits of using quail to study sexual behavior, the use of a visually-oriented species in studying drug effects may be of additional relevance to studying human drug addiction. We currently have preliminary evidence in male Japanese quail that preexposure to cocaine enhances sexual motivation. This finding ties in well with clinical observations that indicate that cocaine use in humans may increase sexual motivation, thereby increasing the likelihood of the occurrence of high-risk sexual behavior. The overall working hypothesis of this proposal is that the magnitude of the sexual response depends on several cocaine preexposure parameters including dose, amount of exposure, time between exposures, and the withdrawal period before sexual behavior testing. Additionally, we hypothesize that cocaine preexposure increases the resistance to extinction (harder to eliminate) and facilitates the reacquisition of a sexual response that has been extinguished. The proposed research has the potential to contribute to our understanding of cocaine preexposure effects on sexual motivation using a visually-oriented animal model. For example, in males, sexual motivation may be enhanced by prior cocaine exposure. Such an enhancement might translate in humans as high risk or compulsive sexual behaviors such as increased frequency of sexual activity, sex with multiple partners, and unprotected sex. These risky sexual behaviors have been linked with considerable health consequences, such as the transmission of HIV and hepatitis C. The goal of the proposed project is to contribute to understanding underlying mechanisms of cocaine's effects on sexual motivation.